1. Field of the Invention
This invention pertains generally to processing pictures, and more particularly to generating and displaying bidirectional prediction pictures, and more particularly to generating and displaying bidirectional prediction pictures using portions of succeeding and prior frames.
2. Description of Related Art
In most video codec systems such as MPEG-2, MPEG-4 and H.264, Bi directional prediction (Bi prediction) is used. Pictures that contain bi-directionally predicted macroblocks are referred to as B pictures, B frames, or B slices. The bi-directional prediction creates a predicted picture from two motion vectors and encoded reference pictures.
In MPEG-2 and MPEG-4, those two reference pictures are motion compensated independently first, then averaged pixel by pixel. In H.264, the weighted prediction mode was introduced where two reference pictures are blended with weights. Because Bi prediction uses two previously encoded pictures, blocks can be encoded efficiently and require fewer bits. Therefore, B slices are often used as a means for reducing bit rates.
The following publications provide useful context for video compression standards, and are hereby incorporated by reference in their entireties.
[1] Flierl, M. and Girod, B., “Generalized B pictures and the draft H.264/AVC video-compression standard,” In IEEE Transactions on Circuits and Systems for Video Technology, Volume 13, Issue 7, Date: July 2003, Pages: 587-597.
[2] Wiegand, T., Sullivan, G. J., Bjøntegaard, G. and Luthra, A., “Overview of the H.264/AVC video coding standard,” In IEEE Transactions on Circuits and Systems for Video Technology, Volume 13, Issue 7, Date: July 2003, Page(s): 560-576.